Place the clams and mussels in a large pan with the wine, cover, and cook over a high heat for 3 to 4 minutes, until they've opened. Discard any that remain closed. Tip everything into a colander placed over a bowl.
Squeeze the tomatoes to remove most of the seeds and juice and then coarsely chop them.
Bring a large pan of well-salted water (1 teaspoon salt to each 2 1/2 cups water) to a boil. Add the linguine and bring back to a boil, then cook for about 8 minutes or until al dente.
Meanwhile, put the olive oil and garlic in a large pan and heat slowly until the garlic begins to sizzle. Add the pepper flakes and tomatoes, and simmer for 5 minutes. Stir in all but the last 1 to 2 tablespoons of the cooking liquid from the clams and mussels. Bring back to a boil and simmer until reduced to a sauce-like consistency.
Stir the langoustines into the sauce and turn them over until they turn pink. Add the shrimp and simmer for 2 to 3 minutes longer, until the langoustines and shrimp are both cooked. Stir in the cooked clams and mussels, along with the chopped parsley, and turn them over a few times until heated through. Season, if necessary, with a little salt and some pepper.
Drain the pasta well and tip it into a large, warmed serving dish. Pour the seafood sauce over the pasta and toss together well. Serve hot.